L6 - Sampling Techniques

Question 1

what is SAMPLING?

Answer 1

PSYCHOLOGICAL STUDIES involve SAMPLES drawn FROM A LARGER POPULATION

TARGET POPULATION is used to describe the GROUP who RESEARCHERS ARE STUDYING and want to GENERALISE THEIR RESULTS TO

SAMPLING TECHNIQUES are used to OBTAIN A SAMPLE of the TARGET POPULATION so that we can avoid studying the ENTIRE POPULATION which would be EXPENSIVE and TAKE TOO LONG.

A SAMPLE should be REPRESENTATIVE of the POPULATION which it is drawn from so that the FINDINGS of the study can be GENERALISED TO THE TARGET POPULATION

Question 2

what is RANDOM SAMPLING?

Answer 2

RANDOM SAMPLING is when EVERY MEMBER of the TARGET POPULATION has the SAME CHANCE OF BEING SELECTED.

The easiest way to do this is to place ALL NAMES FROM the TARGET POPULATION IN A HAT and DRAW OUT THE SAMPLE REQUIRED

Question 3

what are the ADVANTAGES of RANDOM SAMPLING?

Answer 3

The SAMPLE is LIKELY TO BE REPRESENTATIVE and therefore RESULTS CAN BE GENERALISED to the TARGET POPULATION

Question 4

what are the DISADVANTAGES of RANDOM SAMPLING?

Answer 4

It is SOMETIMES DIFFICULT to get FULL DETAILS of a TARGET POPULATION from which to select a sample

Additionally, NOT ALL MEMBERS of the TARGET POPULATION who are SELECTED TO TAKE PART WILL BE AVAILABLE or WILLING TO TAKE PART, making the SAMPLE UNREPRESENTATIVE

Question 5

what is SYSTEMATIC SAMPLING?

Answer 5

SYSTEMATIC SAMPLING is a sampling technique where participants are SELECTED by TAKING EVERY Nth PERSON FROM A LIST

Question 6

what are the ADVANTAGES of SYSTEMATIC SAMPLING?

Answer 6

SYSTEMATIC SAMPLING is FAR SIMPLER THAN RANDOM SAMPLING

Question 7

what are the DISADVANTAGES of SYSTEMATIC SAMPLING?

Answer 7

The PROCESS OF SELECTION can INTERACT with a HIDDEN PERIODIC TRAIT within the TARGET POPULATION

If the sampling technique COINCIDES WITH THE PERIODICITY OF THE TRAIT, the SAMPLING TECHNIQUE WILL NO LONGER BE REPRESENTATIVE

Question 8

what is STRATIFIED SAMPLING?

Answer 8

STRATIFIED SAMPLING involves CLASSIFYING the TARGET POPULATION into CATEGORIES and then RANDOMLY CHOOSING A SAMPLE that consists of PPS FROM EACH CATEGORY in the SAME PROPORTIONS as they APPEAR IN THE TARGET POPULATION

Question 9

what are the ADVANTAGES of STRATIFIED SAMPLING?

Answer 9

the STRENGTH OF STRATIFIED SAMPLING is that ALL GROUPS WITHIN A TARGET POPULATION ARE INCLUDED, therefore the SAMPLE SHOULD BE REPRESENTATIVE of the TARGET POPULATION

Question 10

what are the DISADVANTAGES of STRATIFIED SAMPLING?

Answer 10

STRATIFIED SAMPLING can be VERY TIME CONSUMING as the CATEGORIES HAVE TO BE IDENTIFIED and CALCULATED

If you DO NOT HAVE DETAILS of ALL THE PEOPLE IN YOUR TARGET POPULATION, you would STRUGGLE TO CONDUCT A STRATIFIED SAMPLE

Question 11

what is OPPORTUNITY SAMPLING?

Answer 11

OPPORTUNITY SAMPLING involves selecting pps who are READILY AVAILABLE and WILLING TO TAKE PART

Question 12

what are the ADVANTAGES of OPPORTUNITY SAMPLING?

Answer 12

this is the EASIEST and MOST PRACTICAL METHOD of ENSURING LARGE SAMPLES

Question 13

what are the DISADVANTAGES of OPPORTUNITY SAMPLING?

Answer 13

there is a HIGH CHANCE that the SAMPLE WILL NOT BE REPRESENTATIVE of the TARGET POPULATION

Sometimes people FEEL OBLIGED to TAKE PART in research EVEN WHEN THEY DO NOT REALLY WANT TO, this is UNETHICAL

Question 14

what is VOLUNTEER SAMPLING?

Answer 14

VOLUNTEER SAMPLING involves people SELF SELECTING to participate in a study

The researcher will USUALLY ADVERTISE FOR PEOPLE TO TAKE PART IN THEIR RESEARCH

Question 15

what are the ADVANTAGES of VOLUNTEER SAMPLING?

Answer 15

this can be a USEFUL WAY of finding SPECIFIC PEOPLE TO TAKE PART in PARTICULAR AREAS OF RESEARCH

Question 16

what are the DISADVANTAGES of VOLUNTEER SAMPLING?

Answer 16

A CERTAIN TYPE OF PERSON (people who are interested in the topic or just helpful) TEND TO VOLUNTEER FOR RESEARCH and this means that there is a VERY HIGH CHANCE that the SAMPLE OBTAINED WILL BE UNREPRESENTATIVE (VOLUNTEER BIAS)